Currently, low cost component packaging includes the use of ceramic bolt-down packages, soft substrate bolt-down packages, Printed Circuit Board-based (PCB-based) packages, and over-molded leadframe packages. Over-molded leadframe packages, and particularly quad flat no-lead (QFN) packages, are the least expensive of these package types. The over-molded leadframe package class is known by several terms including, but not limited to, Small Outline Plastic Packages (SOIC), Quarter Size Outline Packages (QSOP), Thin Shrink Small Outline Plastic Packages (TSSOP), Mini Small Outline Plastic Packages (MSOP), Dual Flat No-Lead Plastic Package (DFN), Quad Flat No-Lead Plastic Package (QFN), Small Outline Transistor Plastic Package (SOT), Small Outline Transistor Plastic Packages (SC70-6), Shrink Small Outline Plastic Packages (SSOP), Dual-In-Line Plastic Packages (PDIP), Shrink Dual-In-Line Plastic Packages (SPDIP), Micro Lead Frame Plastic Package (MLFP), Power Small Outline Plastic Packages (PSOP), Plastic Leaded Chip Carrier Packages (PLCC), Metric Plastic Quad Flatpack Packages (MQFP), Thin Plastic Quad Flatpack Packages (TQFP), Thin Plastic Power Quad Flatpack Packages (PQ-LQFP), Single-In-Line Plastic Packages (SIP), and Ball Grid Array Packages (BGA). These over-molded leadframe packages suffer from significant performance degradation in electrical properties at high frequencies, which limits the use of these packages to frequencies below about 15 GHz. These performance degradations include the losses and impedance mismatches caused by the integrated circuit chip/wirebond/printed circuit board interface.
Typical wirebonding out of a QFN package is generally controlled with a single or double wirebond. The wirebond(s) acts as an inductor, or similar circuit, and it is the inductance created by the wirebond that degrades the performance of a typical QFN package. Therefore, a QFN package that reduces or offsets the inductance created by one or more wirebonds is needed.